space-based dtn
DESCRIPTION
Space-based DTN. Low Earth Orbit Results NASA Plans CCSDS Plans Will Ivancic, [email protected] http://roland.grc.nasa.gov/~ivancic/papers_presentations/2008/IETF73_IRTF_DTN.ppt. Secure Autonomous Integrated Controller for Distributed Sensor Webs. - PowerPoint PPT PresentationTRANSCRIPT
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Glenn Research Center Networks & Architectures BranchCommunications Technology
IETF73 - IRTF DTNRG Meeting November 2008
Space-based DTNLow Earth Orbit Results
NASA PlansCCSDS Plans
Will Ivancic, [email protected]
http://roland.grc.nasa.gov/~ivancic/papers_presentations/2008/IETF73_IRTF_DTN.ppt
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Glenn Research Center Networks & Architectures BranchCommunications Technology
IETF73 - IRTF DTNRG Meeting November 2008
VMOC
NOCNOCNOC
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Stored data transferred to
ground Sensor
1Seismic Sensor alerts VMOC
5
Space Sensor acquires data (e.g. image)
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4
4
Network Control Center
Configures Spacecraft via
VMOC
VMOC negotiates for ground station services
VMOC negotiates for ground station services
2 2
VMOC negotiates for Space Assets
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3
Network Control Center
Configures Ground Assets
Network Control Center
Configures Ground Assets
Stored data transferred to ground (Large file transfer over multiple
ground stations)
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Secure Autonomous Integrated Controller for Distributed Sensor Webs
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Glenn Research Center Networks & Architectures BranchCommunications Technology
IETF73 - IRTF DTNRG Meeting November 2008
DTN Test Plan
• Goal– Demonstrate DTN Bundle Transfer from UK-DMC to SSTL Ground
Station– Demonstrate that DTN code and general SSTL code can coexist
without affecting normal SSTL Operations
• Configuration– UK-DMC acquired a150 Mbyte image Cape of Good Hope, South
Africa using the DTN SSDR code. DTN bundling code default set to 80 Mbytes for proactive fragmentation
• Tests1. Basic file download using existing technique (GRC implementation
of Saratoga version 0)2. Same file downloaded but treated as single bundle (DTN)3. Same file download but using DTN proactive fragmentation with 80
Mbytes preconfigured fragments.4. SSTL used their Workstation and SSTL implementation of
Saratoga version 0
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Glenn Research Center Networks & Architectures BranchCommunications Technology
IETF73 - IRTF DTNRG Meeting November 2008
UK-DMC Implementation
Only Bundling and Forwarding
Implemented
Full DTN Protocol Implemented
Surrey Satellite Tech Ltd (SSTL)
Saratoga Client
Test 4
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Glenn Research Center Networks & Architectures BranchCommunications Technology
IETF73 - IRTF DTNRG Meeting November 2008
Bundles on UK-DMC
Payload
DTN Metadata
Proactive Fragmentation Metadata - N
Proactive Fragmentation Metadata - 0
70 - 80 bytes
70 - 80 bytes
70 bytes
70 - 80 bytes
No
t to
Sca
le
150 Mbytes
80 MB
70 MB
N=2
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Glenn Research Center Networks & Architectures BranchCommunications Technology
IETF73 - IRTF DTNRG Meeting November 2008
Palm Island Resort, Dubai, 14 Dec 2003 (UK-DMC)
www.dmcii.com
The Cape of Good Hope and False Bay. False colours – red is vegetation. Taken by UK-DMC satellite on the morning of Wednesday, 27 August 2008.
Downloaded using bundling over Saratoga, with proactive fragmentation. Fragments assembled at NASA Glenn, then postprocessed at SSTL.
First sensor imagery delivered by bundles from space.
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Glenn Research Center Networks & Architectures BranchCommunications Technology
IETF73 - IRTF DTNRG Meeting November 2008
Checksums were very useful
• We implemented manual MD5 checksums over the payload– Greatly aided in debugging
• Identified errors in our Saratoga transport protocol implementation
• Allowed us to prove data was transmitted correctly received without errors – Used for full bundle and reconstituted bundle fragments checking
– 150 Mbytes is a bit to much to manually check
– Checksums can take significant time relative to a satellite pass, thus, we made it a command option• Apparently sometimes SSTL dumps an image and takes
another during the same pass (8 – 12 minutes).
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Glenn Research Center Networks & Architectures BranchCommunications Technology
IETF73 - IRTF DTNRG Meeting November 2008
NASA DTN Fight Readiness by 2011
• Multi-Center Program– JPL, APL, MSFC, JSC, GRC, MSFC, University of Colorado
• Multiple Flight Implementations of RFC 5050 and LTP– JPL, Applied Physics Lab, Goddard Space Flight Center
• Flight Tests– Deep Impact (JPL)– ISS (Bioserve – University of Colorado)
• Desire to get Operations people involved
• Multi-Center DTN Engineering Testbed (DEN)– Strawman Scenarios (Low Earth Orbit, Lunar, Deep Space such as
Mars)
• Technology Development / Research– Network Management
• Also work with DARPA (BBN)• GRC plans to work with DTNRG
– Naming and Routing– Security Issues
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Glenn Research Center Networks & Architectures BranchCommunications Technology
IETF73 - IRTF DTNRG Meeting November 2008
Multi-Center DTN Testbed
GRC plans to put DTN
machines on the OpenNet
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Glenn Research Center Networks & Architectures BranchCommunications Technology
IETF73 - IRTF DTNRG Meeting November 2008
Consultative Committee for Space Data Systems
(CCSDS)
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Glenn Research Center Networks & Architectures BranchCommunications Technology
IETF73 - IRTF DTNRG Meeting November 2008
Organization
• CCSDS consists of Member Agencies, Observer Agencies, Associates and Liaisons.
• A CCSDS Member Agency is a governmental or quasi-governmental organization – Only one agency representing a given country or
multinational organization may participate as a Member Agency of the CCSDS.
– Each CCSDS Agency must formally appoint its delegates to the CCSDS technical Working Groups which that Agency supports
Opinion/ObservationCCSDS patterns itself partially after ITU and partially after IETF
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Glenn Research Center Networks & Architectures BranchCommunications Technology
IETF73 - IRTF DTNRG Meeting November 2008
Organization
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Glenn Research Center Networks & Architectures BranchCommunications Technology
IETF73 - IRTF DTNRG Meeting November 2008
CCSDS Colors / Books
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Glenn Research Center Networks & Architectures BranchCommunications Technology
IETF73 - IRTF DTNRG Meeting November 2008
Space Internetworking Services (SIS) - DTN
• Goal – Determine whether or not “Delay-Tolerant Networking” as specified in
RFC5050 is a feasible solution for a store-and-forward networking protocol for space environments where data relay is likely.• If RFC5050 is lacking in certain specific capabilities, this working
group may define extensions to RFC5050 to address these needs. • If RFC5050 is not suitable, attempt to define an alternate protocol
that meets the needs of the space community.– Use LTP as Transport Protocol– Additional protocols are required in order to provide a complete, working
network. The working group will also produce the following documents:• A Blue Book covering DTN naming and addressing conventions to
be used.• A Blue Book specifying one or more routing protocol(s) to be used
by DTN. • A Magenta Book describing DTN use cases and advice for
applications designers and mission planners.
Great Desire to use RFC 5050 as is in order to speed standardization and maintain interoperability with Earth terrestrial DTNs
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Glenn Research Center Networks & Architectures BranchCommunications Technology
IETF73 - IRTF DTNRG Meeting November 2008
SIS-DTN Schedule (Proposed)
• Spring 2008 CCSDS Meetings Concept paper for discussion.• Fall 2008 CCSDS Meetings
– Green-1 book describing rationale / scenarios / use cases used to evaluate – Red-1 protocols.
• Spring 2009 CCSDS Meetings – Green-2 Book. Goal is to submit this into the publication process by summer 2009.– Red-1 book describing CCSDS Delay-Tolerant Networking protocol – Red-1 book describing reliable hop-by-hop protocol.– Begin initial implementation development as needed.
• Fall 2009 CCSDS Meetings– Final Green Book Approved describing rationale / scenarios / use cases used to evaluate .– Magenta-1 book on advice to application designers and mission planners.– Red-1 book describing naming / addressing conventions.– Begin initial interoperability testing of implementations.
• Spring 2010 CCSDS Meetings– Red-2 Book for CCSDS Delay-Tolerant Networking protocol– Red-2 Book for reliable hop-by-hop protocol.Red-1 books describing DTN routing protocol.
• Fall 2010 CCSDS Meetings– Magenta-2 book on advice to application designers and mission planners.– Second round interoperability testing of DTN and reliable hop-by-hop protocols.
• Spring 2011 CCSDS Meetings– Blue-1 Recommendations (DTN and reliable hop-by-hop)– Red-2 books describing naming / addressing conventions– Red-2 books describing DTN routing protocol.
• Fall 2011 CCSDS Meetings– Final Magenta book on advice to application designers and mission planners.
• Spring 2012 CCSDS Meetings– Blue-1 Recommendation for naming / addressing– Blue-1 Recommendation for routing protocol(s).